I find it funny that so many people on here say, "don't be afraid to do bed baths, dirty work, feeding patients, etc." when I was going to say the opposite. My first few weeks of med surg clinical I was excited to try new things... inserting catheters and IVs, wound care, colostomy care, chest tubes, you name it, I was ready. I was a CNA and med assistant for a few years before nursing school and first semester just seemed like a review of CNA classes. I was ready for the big leagues.
And then I actually got to clinical. The nurses were just using me to do the dirty work while they did all of the things we were supposed to be learning. Or they would pawn us off on the CNAs. They didn't even offer me to let me watch the major skills. But of course I wanted my preceptors to like me so I did everything I could to please them (trust me, I can CNA with the best of them). Meanwhile I wasn't learning anything.
I told my instructor my concern, and she told me I needed to be more assertive. Instead of flat-out saying "no" when a preceptor asked me to do something like a bad bath with a CNA, I just politely said "I would love to do that if we have some down-time later. But I would really prefer to help you because I think it would be more valuable to my learning." I'd also apologize because I know having a student will slow you down if you are teaching them the right way, but will make your day go faster if you make them do the dirty work. I fully acknowledge that. Now, if you haven't done a lot of bed baths or changed a lot of incontinent patients, it probably would be helpful to accept these challenges.
Luckily my instructor gave me the advice to be more assertive before my shift in the ER (each student only got 6 hours in the ER and it was my main interest). Had she not given me this advice, I would have agreed to be the sitter for an elderly woman with dementia and missed out on a TON of stuff, including a trauma patient.
You have to make your education your priority. Is it more important that you gain confidence in your knowledge and skills or is it more important to get a gold star from your preceptor? I probably pissed off a couple preceptors but I learned a heck of a lot more that way. There's a balance. You CREATE opportunities for yourself in nursing school, they don't fall in your lap. If you have even 2 minutes of down time, ask the nurses in the nurses station if they need help with anything or if they have any interesting patients. These are the times I learned the most.